1. Field of the Invention
The present invention relates to a digital broadcast receiver apparatus, digital broadcast receiving method and program, and is preferably applied for automatic station selecting, for example.
2. Description of the Related Art
As shown in FIG. 12, in a system of digital broadcast (FIG. 12A), broadcast programs from a plurality of broadcast stations are multiplexed on one transmission channel (a carrier frequency). This provides more information than a system of analog broadcast (FIG. 12B) in which one transmission channel (a carrier frequency) carries one broadcast program.
In the system of digital broadcast, each station is associated with a different transmission channel (a carrier frequency). As shown in FIG. 13, each base station T1 to T3 superposes a plurality of kinds of broadcast program data PD, which are supplied from an information source IS, on a carrier wave whose carrier frequency is associated with each base station. The stations T1 to T3 subsequently transmit the superposed carrier waves as digital broadcast waves BW1 to BW3. This prevents the digital broadcast waves BW1 to BW3 from interfering with one another.
However, for example, when a digital broadcast receiver device moves from a broadcast area of the base station T1 into a broadcast area of the base station T2, the digital broadcast receiver device may not be able to receive the digital broadcast wave BW2 from the base station T2 even if the base station T2 broadcasts the same program as the base station T1 does because the transmission channel of the base station T2 is different from that of the base station T1.
Accordingly, in the case of the typical digital broadcast receiver device, each time a user moves from one broadcast station T's area to a different broadcast station T's area, he/she has to tune the digital broadcast receiver device to a receivable program in that area, and this could be troublesome to set the device.
One way to solve the above problem is to use the following method: a digital broadcast receiver device registers information, such as program information, location information of transmission stations on Orthogonal Frequency Division Multiplexing (OFDM) modulated signal, and channel frequency information, on itself, and then, when a destination broadcast area broadcasts the same program, the digital broadcast receiver device automatically selects, based on the registered information and various information superposed on a signal received from the base stations, the same program in that area (see Jpn. Pat. Laid-open Publication No. H08-237570, for example).
Accordingly, even if a user moves into a different broadcast area, he/she can watch and listen to the same program there by the digital broadcast receiver device.